Posts Tagged "biosignature"

Two billion year-old water pockets and a revised deep hydrogen content are good news for Earth’s vast subsurface biosphere, and could offer clues to life on Mars and much further beyond. Excitement over the Curiosity rover’s recently reported detection of a ‘spike’ in localized atmospheric methane – persisting over a couple of months – is [...]

Caleb Scharf is the director of Columbia University's multidisciplinary
Astrobiology Center. He has worked in the fields of observational
cosmology, X-ray astronomy, and more recently exoplanetary science. His books include Gravity's Engines (2012) and The Copernicus Complex (2014) (both from Scientific American / Farrar, Straus and Giroux.)
Caleb A. can be found on Twitter as @caleb_scharf.

Astronomers hope that one day soon we’ll obtain a spectrum of light that might tell us whether or not an Earth-sized exoplanet harbors life. This spectrum could be of starlight filtered through the planetary atmosphere, or of reflected and emitted radiation. In either case it would probe the chemical composition of an alien world. The [...]

Caleb Scharf is the director of Columbia University's multidisciplinary
Astrobiology Center. He has worked in the fields of observational
cosmology, X-ray astronomy, and more recently exoplanetary science. His books include Gravity's Engines (2012) and The Copernicus Complex (2014) (both from Scientific American / Farrar, Straus and Giroux.)
Caleb A. can be found on Twitter as @caleb_scharf.

Imagine, if you will, a planet with atmosphere, oceans, rocks and life. On this planet, most chemical reactions are either slow and geophysical, or quick and biological but very localized. There is, however, an exception. Because of the particular nature of this world there is the ever-present potential for a type of chemical reaction that [...]

Caleb Scharf is the director of Columbia University's multidisciplinary
Astrobiology Center. He has worked in the fields of observational
cosmology, X-ray astronomy, and more recently exoplanetary science. His books include Gravity's Engines (2012) and The Copernicus Complex (2014) (both from Scientific American / Farrar, Straus and Giroux.)
Caleb A. can be found on Twitter as @caleb_scharf.